Worried you might not be able to refinance your home mortgage? The federal HARP program helps those with financial stress. Here’s what you need to know.

If you pay your mortgage faithfully even though your home’s value has fallen, there’s a federal refinance program just for you. The latest changes in the federal Home Affordable Refinance Programtarget home owners with a reliable payment history who owe more on their mortgage than their homes are worth.

You can only use HARP if Fannie Mae or Freddie Mac guaranteed your loan before June 1, 2009. If your loan was sold to or guaranteed by Fannie or Freddie after that date, you can’t use HARP.

If you find yourself in any of these five situations, the HARP program can help you take advantage of low interest rates in a mortgage market that might otherwise turn you away:

1. Your income has taken a hit. You used to be a two-income family, but you’re down to one income because of job loss or retirement. The HARP program doesn’t look at how much income you have, only that your household has income.

2. You’re underwater (you owe more on your house than it’s worth). With a HARP program refinance, you can owe more on the value of your house and still refinance. Say your house is worth $200,000 and you owe $250,000. You still get to refinance.

3. You’re fiscally fit. HARP program refinances are limited to home owners who have no more than one late payment in the past year and no late payments in the past six months. Late means you paid 30 days or more after the payment was due. If you have a hard time making your payments, opt for a Home Affordable Modification Program loan instead.

4. You’re stuck in a high-rate loan,so refinancing will either improve your finances by lowering your monthly payment by 5% or more, shift you from an ARM to a fixed rate, or shorten the length of your mortgage (for example, going from a 30-year to a 15-year mortgage). If you won’t benefit, don’t refinance.

5. You’re a landlordand you owe more on your rental property’s mortgage than the home is worth. HARP is one of the few programs that’s refinancing rental properties right now.

Where to get a HARP Program loan

To find a HARP program loan, start with your current lender because some of the biggest mortgage market players only do HARP refinances for their existing mortgage customers.

However, by not shopping around, you might not be getting the best possible interest rate.

Waiting for more lenders to jump into the program before you use HARP may help you get a lower interest rate, but refinancing now means getting that lower monthly payment sooner.

has been writing about real estate for more than two decades. She lives in a suburban Baltimore Midcentury modest home on a 3-acre lot shared with possums, raccoons, foxes, a herd of deer, and her blue-tick hound. Follow Dona on Google+.